//Ultrasonic sensor use
//Vcc to 5v and Gnd  to ground on Arduino.
int tPin=12;      // trigger pin
int ePin=11 ;     // echo pin
float pingTravelTime;
float distance;


void setup() {
  // put your setup code here, to run once:
pinMode (tPin, OUTPUT);
pinMode (ePin, INPUT);
Serial.begin (9600);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite (tPin, LOW);
delayMicroseconds (10);
digitalWrite (tPin, HIGH);
delayMicroseconds (10);
digitalWrite (tPin, LOW);
pingTravelTime= pulseIn (ePin, HIGH);
delay (25);
distance=(pingTravelTime*.3452/2);
Serial.print (" Distance to target is ");
Serial.print (distance);
Serial.println (" mm ");
}